Impeovement in steam-geneeatoss



a S VIMPR om. BQILER.

PATENTED l MAR 31868 FLS, I

SYLVANUS SAWYER, 0F FITGHBURG, MASSACHUSETTS.

Letters Patent No. 75,057, dated ZlIarc/t 3'; 1868.

IMPROVEMENT IN STEAM-{lrENEItAIORS.`

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TO ALL WHOM IT MAY CONCERN:

Be it known that I, SYLVANUS SAWYER, of Fitchburg, in the county of Worcester, and State of Massachusetts, have invented a new'and useful Improvement in Steam-Boilers; and I do hereby declare the following t0 be a full, clear, and exact description thereof, reference being had to the. accompanying drawings, making a part of this specication, in whieh- Figure I is a side elevation of my boilerremovcd from the setting.

Figure 2 is a vertical longitudinal section through the centre of'boiler and the masonry of its setting.

Figure 3 is a vertical transverse section through the fire-box and the setting.

Figure 4 is an end elevation of the boiler and setting, with one-half of `the boiler front, with fire-box and ashpit doors, removed.

In all the drawings' the same letters refer to the same parts.

The subject-matter of my invention relates to an improved mode of constructing boilers for generating steam and other similar purposes, and consists in constructing the tire-box, so called, separate from the main b'oiier, and connecting it with the same by means of steam-chambers, and by suitable steam and water-pipes, so arranged that'whcn the water is at the proper height in thenmain boiler it will entirely fill all that part of the furnace-easing that is directly exposed tc the heat, and also permit the Steam generated therein to pass freely into the main boiler without carrying thev water along. with it; and it also consists in so constructing the water-splace of the furnace-casing, and so arranging the supply and delivery-pipes thereof that the supply of' water will lbe caused to circulate around the furnace before it enters the main boiler, as will be described.

In -tl1e accompanying drawings, my invention is shown in combination' with a tubular boiler, having a cylindrical shell, with the masonry of thefnrnace arranged in a manner not unusual, except so far as to adapt .it to my invention. r

In the drawings, A. is an ordinary tubular boiler, with a cylindrical shell, the lower portion of which is extended forward beyond the line of the front tube-sheet, as shown, and resting upon the front portion of my improved furnace-casing, by which the front end of the'boiler is supported. B is the furnace or fire-box, which is provided with door Naud gratos Q, in the usual manner. It is made with two walls and a water-space, as shown, and does not differ materially from the ordinary form ot' fire-box in common use in boilers, excepting that it is closed at the upper side. The front end is made to I'it the boiler, as shownfbut at the sides and back end there is sutheient space left between them to serve as a ilnc. The water-space, at the frontend of the fire-box, is kdivided in the centre, between the fire-door N and the upper shell of the ire-box, by the partition G, so that all the water entering the furnace-casing through the fced-pipe H must pass to thenear of the water# space, on that side of the fire-box, and through the water-space in the bridge-wall F to the other side, andv then forward to the front end, thus making a complete circuit of the file-box exposed to a high heat before it can enter the main boiler through the pipe I. J is a stcam-drum, attached to the furnace-casing at the front end, which isof the form, in cross-section, shown in ig..4, and rises above the fire-box suilieiently high to afford a steam-space in it above the water-line in the main boiler. It extends for a considerable distance lengthwise of the fire-box, and its lower extremity connects with the water-space of the {irc-box by an opening occupying its.

entire horizontal arca. By means of such free communicationwith the fire-box, the rapid escape of the steam generated by the intense heat inthe fire-box is prevented from lifting-the water, in the form of foam, and discharging it into thc main boiler, thus emptying the` lire-box of its water, and permitting the destruction of its tire-surface by the intense heat of the fire. The steam-'space in the drum is connected with the main boiler by the pipe K. This steam-drum and pipe should bc duplicated on the opposite side of the furnace, at the point M. O is the ash-pit door; I), the door communicating with the smoke-box L. It is the ash-pit, S the smoke-flue under the boiler;V and L the bracket by which the rear end of the mainboiler is supported. U U are the brick walls enclosing the boiler and furnace, provided with the usual bearings or supports for the boiler, and V is the return-smoke iluc over the top of the boiler, and leading to the chimney.

Its evident that my invention may be applied to other forms and styles of boiler than the one represented in the drawings.

The advantages, among others, to be obtained by the use ot' my improved furnace, are-e First, convenience of construction, on account oi' its being made separate from the main boiler.

Second, its applicability to all kinds of boilers which are constructed without iire-box'furnaces, whether new or already in use, with common brick furnaces.

Third, the facility with which the furnace may be replaced when worn out, without disturbing the main boiler. This I consider an important advantage, from the fact; that the furnace is the most perishable part of a steam-boiler, and often requires to bc renewed orveartensively repaired, while the remainder of the boiler is in good condition.

4. The utilization of the heat, which in a brick furnace isllargely absorbed by tbe brickwalls of the firebox, for the purpose of raising the temperature of the water before it enters the main boiler.

What I elaine as my invention, and wish to secure Vby Letters Patent, is-

The combination 'of the detached {irc-box, the steam-drums or chambers, an stantially as described'.

Executed at Boston, thisthirt-'ecnth day of July, 1867.

d the main boiler, arranged sub- SYLVANUS SAWYER.

Witnesses:

N. C. LOMBARD, CEAS. A. JORDAN. 

